1. Field of the Invention
The present invention relates to a kind of air pollution treatment device, and more particularly to an integrative device with two-stage wet-electrostatic process for dust removal-desulfurization, and for removal of soot dust of fuel oil combustion.
2. Description of the Prior Art
With the use of fuel oil instead of coal, the air pollution of industrial and domestic soot dust (black smoke) of fuel oil combustion has become more and more serious. However, since the soot dust (black smoke) of fuel oil combustion is mainly made of soot due to uncompleted combustion, and black carbon and a small amount of impurities formed during combustion process. The soot dust (black smoke) of fuel oil combustion has the characteristics of high temperature (usually 200-300° C.), oiliness, superfine particle (usually <1 μm), small specific resistance (≦103 ohm*centimeter (Ω·cm)) and small density. The soot dust is of poor hydrophilic (hydrophobic nature) and is contained of corrosive gases (such as SO2 and HF). The treatment of the soot dust (black smoke) of fuel oil combustion has always been a technical problem in the field of environmental protection. The existing removal technique of soot dust (black smoke) of fuel oil combustion mainly includes ESP, wet process for dust removal-desulfurization, bag filter and two-stage wet process-electrostatic dust removal-desulfurization. Due to the low specific resistance of the dust (≦103 ohm*centimeter), which is beyond the scope of that of the ESP process (104-5*1010 ohm*centimeter (Ω·cm)), the phenomenon of the black smoke return flow is serious, therefore the technique of ESP has poor efficiency in black smoke removal. As the soot dust has the characteristic of superfine particles and hydrophobic nature, with the wet process for dust removal-desulfurization, the black smoke cannot be removed efficiently too. Though bag filter has a high removal efficiency of black smoke, with the characteristics of high temperature, oiliness and corrosiveness of soot dust, the request for material selection of bag is especially high, and cooling measure is required, all which will result in high construction cost and impossible for simultaneous desulfurization. Therefore, bag filter is rarely used. The newest used two-stage wet type-electrostatic dust removal-desulfurization device, disclosed in CN Pat. No. 03225616.7, has a high efficiency in both dust removal and desulfurization, but due to the soot dust characteristics of low specific resistance, superfine particles and hydrophobic nature, the removal of black smoke is inefficient and cannot reached the requirement of environmental protection.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.